Aircraft fuselage structures are disclosed in DE 10 2006 051 572 A1 and/or US 2011/0266398, which the present disclosure relates to, wherein the publications describe the suspension of the aircraft torsion box on the fuselage structure.
In particular in transport aircraft, it is desirable to configure the transport aircraft as so-called high-wing planes in which the wings are connected to the fuselage in the upper region thereof. A reason for this is that in transport aircraft the loading takes place from the rear and a low loading edge and/or a short distance between the ground and the floor in the aircraft should be present. Moreover, the ground clearance of the propulsion units and optionally the propeller drives have to be sufficient. In this case, the high-wing plane represents an optimal compromise in terms of flow technology between the minimum fuselage cross section and the uninterrupted fuselage, i.e. maximum cargo area.
However, it is also desirable that the wing torsion box, on which the support surfaces are attached and are connected to the fuselage, is not located completely outside and/or above the actual fuselage structure. Otherwise, a relatively high air resistance would result. If the wing torsion box, however, extends transversely through the upper part of the fuselage structure, it is either necessary for the ribs at this point to extend deeper into the internal space in the upper region of the fuselage structure or for the ribs to have to be interrupted in this portion. The first alternative has the drawback that the height of the fuselage internal space is markedly reduced in the region of the wing torsion box. The second alternative represents a requirement with regard to the structural engineering of the aircraft.
In any case, however, the outer skin is interrupted in the upper region although this region has to absorb substantial portions of the loads occurring in the longitudinal direction. This problem is accentuated further when the fuselage is intended to be configured as a so-called pressure fuselage, i.e. a pressure is able to be built inside the fuselage which is above ambient pressure so that the aircraft is also able to fly at high altitudes without passengers and crew having to use breathing apparatus. As a result, however, it is necessary to seal the recess to the wing torsion box, and it has to be ensured that the recess does not deform under load to such an extent that the sealing element incorporated therein is detached from the edge of the recess.
A problem similar to that described above may occur in low-wing planes. In this case, however, the recess in the fuselage is provided in the downwardly facing part.